Question

2sen(x)cos(x)-cos(x)=0

Answer 1

2.sen (x).cos (x)-cos (x)=0
cos x.(2sen x-1)=0

Obtenemos el famoso 0 con dos formas;
cosx=0 x= arc cos 0=90º+kπ
(2 sen x-1)=0 sen x=1/2 x=arco sen (1/2)=30º +2Kπ U 150º+2Kπ

Answer 2

2sen(x)cos(x)-cos(x)=0

2sen(x)cos(x)=cos(x)

2sen(x)=cos(x)/cos(x)

2sen(x)=1

sen(x)=1/2

x=30 -----> sen 30 = 1/2